Works like magic…but it's science! Harmony Pet Litter Box Calming Diffuser is portable, requires no plug, no batteries and no messy cords. And best of all, it attaches directly to the litter box to stop aggression in multi-cat households, promote calming, and attract cats to the litter box. Harmony Pet Home Diffuser for Cats will deliver calming benefits for up to 30 days and helps to reduce stress related behaviors. No plug required! Harmony Pet's calming pheromone has been clinically studied and proven to be 2.5 times more effective than leading brands in reducing stress.